Method of locating vascular obstructions



June 18, 1957 J. H. NORDSTROM 2,796,525

METHOD OF LOCATING VASCULAR OBSTRUCTIONS Filed July 17, 1956 Fig 5 IN VEN TOR.

John H Nora's/ram Af/j United States Patent IVIETHOD OF LOCATINGVASCULAR OBSTRUCTIONS John H. Nordstrom, San Francisco, Calif.

Application July 17, 1956, Serial No. 598,354

2 Claims. (Cl. 250-65) This invention relates to improvements in meansfor locating restrictions affecting the flow of blood in the human body.

The principal object of this invention is to provide means forsimultaneously recording distance and rate of flow of blood in the humanbody, as for instance, through one of the principal arteries thereof.

A further object is to produce a device of this character which isautomatic in operation and synchronized with X-ray exposures so as toinclude on the exposed film not only the shadow graph of the humanartery, but also a shadow graph of a time interval, and to perform thisoperation in rapid succession whereby the rate of flow and the timeinterval involved may be accurately determined.

Other objects and advantages will be apparent during the course of thefollowing description.

In the accompanying drawings forming a part of this specification and inwhich like numbers are employed to designate like parts throughout thesame,

Fig. l is a perspective view of my time indicator;

Fig. 2 is a cross sectional view through the indicator, as the samewould appear on the X-ray table, which table and a portion of the tableand cassette are shown in cross section;

Fig. 3 is a fragmentary top plan view on an enlarged scale of my timingwheel and showing the casing in cross section;

Fig. 4 is a diagrammatic side elevation of a human artery and having arestriction therein; and

Fig. 5 is a fragmentary elevation of an exposed X- ray film having ashadow graph thereon which indicates the flow of dye-carrying bloodthrough two of the major arteries.

In the diagnosis of various infirmities it is often necessary todetermine through the use of X-rays whether the condition is broughtabout by some growth pressing upon one of the arteries which feeds bloodto a certain area, or whether it is caused by some vascular conditiondirectly attributable to the artery itself, and to determine at whatpoint this condition is occurring so that a proper diagnosis may bemade.

Applicant has therefore devised a means of registering a time indicatordirectly upon the X-ray film which time indication will coincide withthe exposure so that the difference between successive exposures willdetermine the distance the dye-carrying blood has flowed between thetime that the two exposures were made.

In the taking of several exposures, it may be found that the blood willflow at a definite rate up to the point of restriction and that adefinite dilferent rate will occur in the multiple exposures taken afterthe restriction has been passed, which in itself will pinpoint the pointof restriction.

In the accompanying drawings, wherein for the purpose of illustration isshown a preferred embodiment of my invention, the numeral 5 designatesthe casing of my device which is made of a material which does notmaterially impede the rays from the X-ray machine. Within this casing Iposition a motor 6 is geared to a shaft 7 from which is suspended awheel 8 freely rotatable on the shaft 7 and connected to the shaftthrough the medium of a spring 9, the purpose of which will be laterseen.-

The support 11 for the motor serves to suspend a stop pin 12 which is inalignment with a pair of pins 13 carried in the upper surface of thevwheel 8. This wheel also carries numerical indicia 14 which areimpervious to X-rays and will therefore cast a shadow. Lead pellets 16are also imbedded adjacent the periphery of the wheel, which leadpellets will also cast shadows on the X-ray film.

The base 17 has a lead pointer 18 which will underlie the forward edgeof the wheel 8. The casing 5 is secured to the base 17 in any desiredmanner.

The motor 6 has a clutch member 19, the purpose of which is to permitthe spring 7 to reset the wheel to the point zero after power is turnedofi from the motor.

The motor is activated through the medium of closing a switch 21permitting current to flow from the current source to the motor. As asafety feature, the motor is grounded by the wire 22.

In use my device is positioned on the X-ray table 23 at a point wherethe forward part of the casing 5 containing the wheel 8 overlies theX-ray film 24 mounted either in a cassette or in a film holder. In thepresent instance I have shown a cassette 26 slidably supported bybrackets 27, one of which is shown in the drawing mounted beneath thetable 23.

As is well known, a cassette is merely a film holder having a pair ofopaque slides 28 which protect the film from exposure to rays ofordinary light.

In Fig. 4 I have shown diagrammatically in cross section an arteryhaving a restriction at the point A. It is of course understood thatthis restriction may be caused by one of many different occurrences, forinstance by the building up of deposits within an artery, or by pressureupon the artery from other causes.

It is here to be noted that the rate of flow could be two inches asecond to the left of the point A in the Fig. 4 and one and a halfinches per second to the right of the point A, which fact would indicateand pinpoint the area where the restriction occurs.

Referring now to Fig. 5, we will assume that an X- ray exposure has beentaken with the result that on the exposed film after development We willfind a picture which in the present instance shows an artery B and anartery C, and also a shadow graph of the wheel 8, which shadow graphshows that the wheel has turned so that for instance 10 seconds of timehave elapsed between the time that the motor 6 was energized and thetime the picture was taken. It is to be here understood that during this10 seconds there have been a number of X-rays taken and that just priorto the taking of the initial exposure, an opaque dye was inserted in theartery B. The result is that the shadow graph of the artery B will showjust how far said dye has progressed along the artery. The shadow graphand the time indicator being exposed simultaneously will give a definitedistance that the blood has traveled between the instant exposure andprevious exposures or future exposures. Then by measuring the rate oftravel, as for instance, if an obstruction has occurred, the rate oftravel will decrease and at the point of decrease is the spot where theobstruction must of necessity be located.

Consequently, by this method, the point of restriction is known and itis necessary only to make an incision to determine the cause of therestriction, which hasnot been possible heretofore.

It will thus be seen that I have accomplished all of the objects aboveset forth. It is to be here understood that the form of vrny inventionherewith shown and described is to -be taken as a preferred example ofthe same and that various changes relative to the material, size, shapeand arrangement of parts may be resorted to Without departing from thespirit of the invention or the scope of the subjoined claims. v V

Having thus described my invention, I claim: I e

1. A method of locating a vascular obstruction in a 4 r i bodycomprising the injection of a dye into 'theblood stream, thence theexposing of a series of X-ray films in rapid succession and impressingsimultaneously on each successive film a shadow graph of atime-controlled moveable indicator and the dye-carrying blood.

2. Means for locating a vascular obstruction comprising a series ofrapidly exposed X-rays, each having simultaneously impressed thereon atime-controlled indicator shadow graph and a shadow graph of adye-carrying blood artery whereby the rate of flow of dye-carrying bloodmay be measured in the successive exposures.

No references cited.

